FIG. 2 is a cross sectional view of conventional induction heating device 5001. Top plate 2 for placing object 2, such as a pot, to be heated thereon is provided on an upper surface of housing 1. Heating coil 4 is for inductively heating object 2 is provided under top plate 3. Heating coil 4 is divided into inner coil 4A and outer coil 4B electrically connected to each other. Sensors 5, thermal sensing elements, such as thermistors, are provided on a lower surface of top plate 3 at a center area of heating coil 4, i.e., a center area of inner coil 4 and at an area between inner coil 4A and outer coil 4B. Sensors 5 are placed below object 2 and output signals in response to a temperature of object 2. Temperature calculator 6 calculates a temperature of object 2 based on the output signals. Controller 7 controls an electric power supplied to heating coil 4 based on the calculated temperature. Patent Document 1 discloses a conventional induction heating device including two sensors.
In the case that object 2 is not positioned directly above at least one sensor 5, conventional induction heating device 5001 has less heat responsiveness and less temperature detection accuracy of sensor 5 than the case that object 2 is positioned directly above sensors 5. In this case, induction heating device 5001 may not heat object 2 accurately at a predetermined temperature.    Patent Document 1: Japanese Patent Laid-Open Publication No. 2003-234168